What Is a Digital Human?
A Digital Human is a synthetic replica of a customer that interacts with your agent during Bluejay simulations. Each Digital Human carries an intent, success criteria, and a set of behavioral traits that together form a single, self-contained test case. Digital Humans are the atomic unit of testing on Bluejay. A simulation runs one or more Digital Humans against your agent, producing a transcript and evaluation result for each interaction.Digital Human Fields
Every Digital Human is defined by the following fields:| Field | Type | Description |
|---|---|---|
| Intent | String | What the Digital Human wants to accomplish in the conversation |
| Success Criteria | List | Conditions that must be met for the interaction to be considered successful |
| Language | String | The language the Digital Human speaks (e.g., English, Spanish, Mandarin) |
| Accent | String | Regional accent applied to speech (e.g., British, Southern US, Latin American) |
| Emotion | String | Emotional tone (e.g., Calm, Frustrated, Anxious, Angry, Cheerful) |
| Speaking Speed | String | Pace of speech (Slow, Normal, Fast) |
| Volume | String | How loud the Digital Human speaks (Quiet, Normal, Loud) |
| Background Noise | String | Ambient sounds during the call (Office, Airport, Car, None) |
| Scripted Responses | Map | Trigger-response pairs for deterministic behavior |
| DTMF Sequences | List | Touch-tone codes to send during the call |
| Silence Duration | Number | Seconds the Digital Human stays silent at a specified point |
| Allow silence tool | Boolean | When true, the voice runtime may use the silence tool for this digital human (subject to execution-layer rules) |
| Silence tool instructions | String | Use "default" for built-in silence-tool behavior; otherwise custom instructions for the runtime. Distinct from scripted silence duration above |
How Bluejay Generates Digital Humans
When you use the generation endpoint, Bluejay creates Digital Humans based on the context you’ve provided about your agent. The generation process works in three stages:Context ingestion
Bluejay reads your agent’s description, system prompt, goals, and any existing Digital Humans to understand the problem space.
Scenario diversification
The generation engine creates a diverse set of intents and customer profiles, varying across languages, emotions, complexity levels, and scenario types.
Intent Design
A well-written intent is specific, actionable, and reflects a real customer scenario. Here’s how to think about writing intents: Weak intent:Success Criteria Design
Success criteria should be specific, observable, and binary. Each criterion should be something Bluejay can evaluate from the transcript alone. Good criteria:- The agent acknowledged the duplicate charge within the first 3 turns
- The agent offered a refund or escalated to billing
- The agent did not share account balance before verifying identity
- The agent was helpful
- The conversation went well
- The agent sounded professional
Scripted Responses vs. Natural Conversation
Digital Humans support two conversation modes:Natural conversation
The Digital Human responds dynamically based on its intent and traits. Best for exploratory testing and discovering unexpected agent behaviors.
Scripted responses
The Digital Human follows a predetermined script, responding with specific phrases when triggered. Best for regression testing and deterministic validation.
Communities
Digital Humans can be grouped into Communities — reusable sets of personas that form a benchmark population. Communities enable:- Consistent benchmarks — run the same set of Digital Humans against different agent versions to compare performance over time
- Audience segmentation — organize Digital Humans by customer type, language, or scenario category
- Cross-agent testing — use one Community across multiple agents to see how different agents handle the same customers
Best Practices
Start with your real customers
Review your production call logs, support tickets, and customer feedback. Build Digital Humans that reflect the actual scenarios your agent encounters.
Cover the full spectrum
Don’t only test the happy path. Create Digital Humans for edge cases, adversarial scenarios, multilingual interactions, and silence/timeout conditions.
Be specific with success criteria
Vague criteria produce vague results. Write criteria that are observable in a transcript and leave no room for interpretation.
Iterate and expand
Start with a small set of targeted Digital Humans. As you discover new failure modes in production, add corresponding Digital Humans to your simulation suite.
API Reference
Create
Create a single Digital Human with full configuration.
Generate
Auto-generate up to 100 diverse Digital Humans.
Update
Modify an existing Digital Human’s fields.